The worldwide proliferation of wireless (or "mobile") telecommunications services is a result of substantial cost breakthroughs in mobile telecommunications terminals, more commonly known as "wireless telephones". The cellular principle has also contributed to the growth of wireless telecommunications by enabling voice and data to be carried over an allocated radio spectrum to cell sites located across far-reaching geographic areas. Indeed, mobile subscribers use their wireless telephones most everywhere and expect service features to be accessible wherever wireless service is provided.
This expectation of readily available access to service features poses a significant problem for wireless telecommunications service providers. This is because all wireless telecommunications systems do not share a common air interface protocol. Therefore, roaming mobile subscribers (that is, those subscribers who access wireless services outside the geographic area served by their "home" system) must initiate the application of service features, such as call forwarding or voice mail, using different procedures than those used in their home system. There is also a possibility that some wireless telecommunications systems do not offer all the service features to which the roaming mobile subscribes. This inaccessibility to service features prohibits optimum use of wireless telephones and causes mobile subscriber inconvenience.
Therefore, there is a need in the art for providing wireless telecommunications services subscribers universal access to service features wherever wireless telecommunications services are provided.